Let's see if we guess where this spawn comes from. It may be a mistake for icing sugar ("impalpable sugar") , which would be what in French is called glace (glas "snowy" ); but it could also be a half-baked translation of the English sugar glass that is used for special effects, since it looks like a real glass cloth, but in truth it is made with sugar and the stunts in the movies can go through them (p. and. in a window) without risk of being cut as with a real glass.
